Tool vibrating means



April 7, 1942.

IIKVENTORS'.

J. E. KLINE ETAL TOOL VIBRATING MEANS Filed May 24, 1939 I MY? 1 k M N \mww A TTORNE Y w Y B Patented Apr. 7 7, 1942 TOOL VIBRATING S John E. Kline, Grosse Pointe Farms, and Douglas T. Peden, Ann Arbor, Mich, assignors to Micromatic Hone Corporation, Detroit, Mich, a corporation of Michigan Application May 24, 1939, Serial No. 275,519

7 Claims. (Cl. 51-59) Our invention relates to a grinding device and particularly to a unit device for reciprocating an abrading stone on the outer surface of a cylindrical element.

For the purpose of obtaining very accurate 1 dimensions, contour, and finish on the surface of a cylindrical workpiece, a device is employed for changing a motion in rotation to one in translation for reciprocating an abrading stone longitudinally on the outer surface of a cylindrical workpiece. The device is preferably mounted in a standard whichmay be moved toward and away from a workpiece and to be fed therealong during the time the abrading stone is being reciprocated. The device may be attached to the table of a grinding machine adjacent to the grinding stone thereof to follow the grinding stone across the workpiece surface to perform a finishing operation as the surface is being rough finished by the grinding wheel.

The device embodies an eccentric shaft supported in a casing which in turn is supported by a housing containing a motor having a train of reduction gears associated therewith for driving the shaft in rotation. -The eccentric end of the shaft projects into an end of a wobble arm which is supported medially of its length in a, ball'socket, with the extending end disposed to actuate a slide in reciprocation. An abrading stone is retained on the outer face of the slide for tilting movement by suitable spring means. The device rapidly reciprocates the abrading stone, and can be supported by hand to produce a finish on a cylindrical surface, but which is preferably supported in a standard and accurately adjusted relative to a surface, to not only produce a fine finish but also to machine to an accurate dimension.

Accordingly, the main objects of our invention are to provide a self-contained unit for driving an abrading element in reciprocation longitudinally of its length; to mount a unit element which drives an abrading stone in reciprocation on a standard which supports the element for axial adjustment; to mount a shaft having an eccentric on one end in bearings in a housing supporting a driving element which is attached to the opposite end of the shaft and connect a wobble arm to the eccentric for the purpose of changing a movement in rotation to one in translation; to provide a slide in the end of the tool to which the end of the oscillatable wobble arm is secured, having a support thereon for an abrading stone which permits the stone to tilt normal to the axis of the device; and in general, toprovide a unit device for which is simple in construction, positive in operation, and economical to manufacture. Other objects arid features of novelty of o invention will be specifically pointed out or will become apparent when referring, for a better understanding of our invention, to the following description taken in conjunction with the accompanying drawing, wherein: V

Figure 1 is a side view of a device embodying features of our invention mounted adjacent to a grinding stone with its abrading end in contact with the workpiece to be finished;

Fig. 2 is an enlarged sectional view of the device illustrated in Fig. 1;

Fig. 3 is an enlarged sectional view of the structure illustrated in Fig. 2, taken on the line 3-3 thereof;

Fig. 4 is an enlarged sectional view of the structure illustrated in Fig. 2, taken on the line 6-5 thereof;

Fig. 5 is an exploded view in perspective of the left-hand end of the tool illustrated in Fig. 2; and

Fig. 6 is an enlarged sectional view of the'structure similarly illustrated in Fig. 2, showing a modified form of the left hand end portion thereof.

The tool it], illustrated in the figures, embodies a housing H in which a bearing supporting element I2 is retained by the threads i3. A roller bearing M abuts against the shoulder l5 at the lower end of the element, while, an upper hearing it abuts against the shoulder ii of the element An oil seal 88 is mounted below the bearing to for sealing a shaft H which is supported by the bearings l4 and IS. The shaft has an enlarged end 2| on the left, as viewed in the figure, from which an angularly disposed crank arm 22 extends. The opposite end of the shaft has a threaded portion 23 on which anut 24 is threaded for clamping the shaft to the inner ra'ceways of the bearing.

A driving end 25 on the shaft has a keyway 26 into which projects a key 21 which is supported on a threaded collar 28 threaded upon the stub end 29 of a shaft 3| of a driving element 32. A look nut 33 locks the threaded sleeve 28 to the shaft. A housing 34 is attached to the right hand end of the housing I! by a screw 35 which draws the sides of the split portion 36 about the housing l I. The opposite end of the housing 36 is split at 3land is clamped about the housing of the driving element 32 by a screw 38., The driving element 32 is of conventional form having a motor 39 operating through a train of -gears M for reducing the speed developed by the motor when rotating the shaft l9, while increasing the driving torque.

On the left hand end of the housing II, a

wobble arm 42, having a semi-spherical portion 43, is supported in a collar 44, having a semispherical mating aperture 45 which receives portions 43 of the arm. A spring 46 is retained on the arm by a pin 41 which urges the semispherical portion 43 into the aperture. The upper end of the arm has pinned thereto a bifurcated element 48, the ends 49 of which have cylindrical surfaces 51. A raceway 52 of truncated spherical 'form is received within with the surfaces 5| and contacts the end of the crank arm 22 through bearings 53 of the needle type. The raceway 52 is supported by the surfaces 5| through the adjustment of a screw 54 which draws the bifurcated ends 49 toward each other. The arrangement is such that the resistance imparted to the raceway 52 by the cylindrical surfaces 5! is greater in the plane of oscillation of the arm 42 and of a lesser degree in a plane transverse thereto. The guides42 maintain the oscillating movement of the arm 42 in a flxed plane. The degree of wobble or oscillation t0 the arm 42 is adjusted by changing the longitudinal position of the crank arm or pin 22 through the adjustment of the sleeve l2 in the casing Ii. This adjustment changes the effective radius of the crank arm or pin to increase or decrease the effective circles described thereby.

The lower end of the wobble arm 42 terminates in a ba1l 56 which is disposed in an aperture in a slide 58. The slide is provided with projecting flanges 6| which operate in slots 52 in the end of a sleeve 63 having a shoulder 55 supported against the end of the housing H by a flanged nut 64. A pin 66 projecting from the enlarged end portion 61 of the sleeve 63 extends within a slot 68 in the end of the housing for positioning the sleeve thereon. The slide engages a block Ii having projecting flanges 12 which extend over the faces 13 of the slide to form a driving connection therewith. The opposite face of the block has arcuate end portions 14 which engage the annularly disposed surfaces 15 on the backing element I5 of the abrading stone.

The slide 59 has a side wall slotted at 18 in which side projecting portions I9 on the backing element 16 project to provide a driving relation therebetween. The side projecting portions 19 have the portion in engagement with the wall 18 of arcuate shape to permit the backing element to tilt on the arcuate surfaces 14 and the face of the stone to adjust itself relative to the surface of the workpiece. Projecting fingers 9| extend from the slide 58 and from the backing element 16 which are connected by springs 82 for supporting the backing element on. the slide while permitting the tilting of the element on the block.

In Fig. 6 we have illustrated a slightly modified form of wobble element 85 supported between the guides 95 directly in the housing 85, which is similar to the housing Ii above described. The end of the sleeve 95 is slotted at 91 and has arcuate elements 99 secured to the side walls. The elements 89 and the edge 90 of the housing are provided with slots 9! in which the projecting flange 5| of the slide 58 is supported for movement in reciprocation or vibration. An annular collar 92 is slidably disposed within the end of the housing 85 and has a truncated spherical aperture 93 which receives the spherical portion 43 of the wobble arm 95. A spring 94 is supported in the housing on a washer retained in position by a clamping ring 96. The spring urges the annular sleeve 92 upwardly to provide a spring support for the wobble arm. Otherwise, the device is the same as that illustrated and described relative to Figs. 1 to 5, inclusive.

The device just described produces a fast reciprocation in the order of a vibration to an abrading stone, axially of its length. A movement in rotation from a driving motor, which is part of the unit, is changed to one in reciprocation through a shaft having an eccentric end engaging a wobble arm. By selecting the proper train of gears, by regulating the length of the wobble arm on either side of its pivot point, or by varying the speed of the motor, the speed of vibration of the abrading stone in reciprocation may be adjusted. Mounting means may be provided for the self-contained device which is preferably adjustable to move the device axially toward and away from the work. The adjustable support is preferably mounted on a bed which may be raised and lowered and moved toward and along the workpiece. While the device may be supported by hand, such mounting means is more desirable so that the workpiece may be accurately machined to a desired dimension.

While we have described and illustrated but two embodiments of our invention, it will be apparent to those skilled in the art that various changes, omissions, additions, and substitutions may be made therein without departing from the spirit and scope of our invention, as set forth in the accompanying claims.

We claim as our invention:

1. A unit device for oscillating a machining element embodying a casing, a shaft rotatably journaled in the casing, an eccentric end on said shaft, a wobble arm in extension of said end oscillated thereby, a slide mounted in said casing for reciprocation by said wobble arm, and means for supporting said machining element on said slide.

2. A unit device for oscillating a machining element embodying a casing, a shaft rotatably journaled in the casing, an eccentric and on said shaft, a wobble arm in extension of said end oscillated thereby, a slide mounted in said casing for reciprocation by said wobble arm, means for supporting said machining element on said slide, and motor means carried by said casing and connected to said shaft.

3. A unit device for machining the surface of a workpiece embodying a casing, a rotatable shaft journaled therein, motor means carried by said casing for driving said shaft in rotation, a machining element supported by said casing for movement in reciprocation, and means aligned with said shaft and interconnecting said machining elements with said shaft for changin, the movement in rotation to one in reciprocation of said element.

4. A unit device for machining the surface of a workpiece including, in combination, a casing, a shaft having an eccentric end journalled in said casing, a wobble arm supported interjacent its ends in extension of said shaft for universal movement having a driving connection with said eccentric, a slide reciprocally supported in said casing and connected to said wobble arm, and a machining element supported on said slide for tilting movement.

5. A self contained tool embodying a motor, a casing supporting said motor, a shaft driven in rotation by said motor; a slide supported for reciprocal movement, by said casing, means in extension of said shaft interconnecting said slide and shaft to change a movement in rotation of the shaft to one of reciprocation of the slide, and an abrading element supported on said slide, the contact between said slide and element being such as to permit said element to tilt relative to said slide.

6. A self-contained tool embodying a casing; a rotatable shaft in said casing, a crank arm on said shaft dispose w, at an angle thereto, a wobble'arm mounted said casing oscillating 

